The asymmetric unit of the title compound, C11H10O3, contains two crystallographically independent molecules, A and B, with closely matching conformations (r.m.s. overlay fit = 0.105 Å). In each case, the OH group of the acetic acid residue occupies a position approximately antiperiplanar to the C atom of the heterocycle. A short intramolecular C—H...O contact occurs within each molecule. In the crystal, carboxylic acid A+B dimers generate R22(8) loops.
